标题： 一种受激和自发轴子散射的理论 显示英文标题

标题： A theory of Stimulated and Spontaneous Axion Scattering

摘要： 我们提出了一种理论，用于非线性共振激发由反向传播电磁波在破坏$\mathcal{P}$和$\mathcal{T}$对称性的材料中的动态轴子。 我们表明，动态轴子可以介导低频（斯托克斯）光束振幅的指数增长。 我们还讨论了在单个泵浦激光存在下，通过量子和热涨落的共振放大，可以自发生成反向传播的斯托克斯模式。 值得注意的是，这种放大可以比受激布里渊和拉曼散射过程获得的放大高几个数量级，并且可以通过施加外部磁场进行调制，这使得受激轴子散射在光电子学应用中具有前景。 显示英文摘要

摘要： We present a theory for nonlinear, resonant excitation of dynamical axions by counter-propagating electromagnetic waves in materials that break both $\mathcal{P}$ and $\mathcal{T}$ symmetries. We show that dynamical axions can mediate an exponential growth in the amplitude of the lower frequency (Stokes) beam. We also discuss spontaneous generation of a counter-propagating Stokes mode, enabled by resonant amplification of quantum and thermal fluctuations in the presence of a single pump laser. Remarkably, the amplification can be orders of magnitude larger than that obtained via stimulated Brillouin and Raman scattering processes, and can be modulated with the application of external magnetic fields, making stimulated axion scattering promising for optoelectronics applications.